It finally happened. Some college students tried to shout down a campus speaker whose views they didn’t agree with — in this case Nonie Darwish, an Egyptian-born anti-Jihad crusader — and the pro-speaker crowd at the University of New Mexico responded with violence toward the interrupters. Audience members snatched papers from the protesters and shoved them out of the lecture hall.

The videos don’t capture everything clearly, but one seems to show a silver-haired man flinging a college-age protester to the floor (Go, Grandpa, go!). Such an incident was inevitable. Audiences subjected to loutish attempts to silence speakers were usually passive in the past. They have been getting more aggressive lately, often drowning out the offenders with shouts of “U.S.A.! U.S.A.!” This time, they got physical.

The New Mexico protesters complained about the audience members’ violence, but they brought it upon themselves. Interrupting or silencing legitimate campus speakers is itself an act of violence, in that it physically denies the right of free speech and assembly, and is therefore an invitation to even greater violence in return. Unless schools start realizing this new potential for violence and start enforcing rules with some teeth (such as expulsion for anybody participating in an attempt to interrupt or silence speakers), somebody is likely to get seriously hurt.